AP Environmental Science — Unit 1: The Living World: Ecosystems

Q1. (ID: ap_environmental_science_MCQ_U1S9Q1)
A local ecosystem has a total biomass of producers equivalent to $10,000 \text{ kg}$. If energy transfer efficiency between trophic levels is $10\%$, how much energy, in terms of biomass, would be available to secondary consumers?
Q2. (ID: ap_environmental_science_MCQ_U1S9Q2)
A detailed diagram illustrating the global carbon cycle. Key reservoirs like the atmosphere (carbon dioxide), oceans (dissolved carbon, marine organisms), terrestrial biosphere (plants, soil, animals), and fossil fuels (coal, oil, gas) are clearly labeled. Key processes such as photosynthesis, respiration, decomposition, combustion (from fossil fuels and biomass), ocean uptake, and volcanic activity are represented by arrows connecting the reservoirs. The arrows are distinctly labeled with the names of the processes. The overall composition is clean and educational.
Which of the following processes removes carbon from the atmosphere and incorporates it into organic molecules?
Q3. (ID: ap_environmental_science_MCQ_U1S9Q3)
A detailed and scientifically accurate diagram of the nitrogen cycle. Key reservoirs should include the atmosphere ($N_2$), soil (ammonia, ammonium, nitrites, nitrates), and living organisms (plants, animals). Essential processes depicted by clearly labeled arrows are nitrogen fixation (by bacteria, lightning), ammonification, nitrification, assimilation (by plants), consumption (by animals), and denitrification. Different types of bacteria involved (e.g., nitrifying, denitrifying, nitrogen-fixing) are implied by the process labels. The diagram uses a clear and professional color scheme.
Which of the following processes in the nitrogen cycle converts atmospheric nitrogen ($N_2$) into ammonia ($NH_3$), making it usable by plants?
Q4. (ID: ap_environmental_science_MCQ_U1S9Q4)
A simple linear food chain diagram. It starts with
The diagram shows a simplified food chain. If the grass contains $10,000 \text{ units}$ of energy, approximately how much energy would be available to the snake?
Q5. (ID: ap_environmental_science_MCQ_U1S9Q5)
Which of the following describes a symbiotic relationship where one species benefits and the other is neither harmed nor helped?
Q6. (ID: ap_environmental_science_MCQ_U1S9Q6)
A generic climatograph without specific biome labels. The x-axis represents months (Jan-Dec). The left y-axis represents average monthly temperature in degrees Celsius (ranging from -20 to 30). The right y-axis represents average monthly precipitation in millimeters (ranging from 0 to 400). A line graph shows temperature remaining consistently high, above 25 degrees Celsius, throughout the year. A bar graph shows precipitation remaining consistently high, above 200 mm, throughout the year. Clear gridlines are present.
A climatograph for a particular biome shows consistently high temperatures ($>25^\circ \text{C}$) year-round and high precipitation ($>200 \text{ cm/year}$). Which biome is best represented by these characteristics?
Q7. (ID: ap_environmental_science_MCQ_U1S9Q7)
Which of the following aquatic biomes is characterized by shallow, nutrient-rich water, high productivity, and emergent vegetation?
Q8. (ID: ap_environmental_science_MCQ_U1S9Q8)
A clear and simple food web diagram. Organisms include: Grass, Berries, Grasshopper, Mouse, Rabbit, Snake, Hawk. Arrows show energy flow: Grass to Grasshopper, Mouse, Rabbit. Berries to Mouse, Rabbit. Grasshopper to Snake. Mouse to Snake, Hawk. Rabbit to Hawk. Snake to Hawk. All organisms are represented by simple drawings or text labels, with arrows indicating the direction of energy flow.
Based on the food web provided, which organism functions as both a primary and secondary consumer?
Q9. (ID: ap_environmental_science_MCQ_U1S9Q9)
What is the primary way that solar energy is captured and converted into chemical energy in most ecosystems?
Q10. (ID: ap_environmental_science_MCQ_U1S9Q10)
A detailed and educational diagram of the phosphorus cycle. Key reservoirs should include rocks, soil (phosphate ions), water bodies (dissolved phosphates), and living organisms (plants, animals). Essential processes depicted by clearly labeled arrows are weathering of rocks, absorption by plants, consumption by animals, decomposition, and sedimentation. There should be a clear indication that there is no significant atmospheric component to this cycle.
Which of the following is a major reservoir for phosphorus in the phosphorus cycle?
Q11. (ID: ap_environmental_science_MCQ_U1S9Q11)
In a particular ecosystem, primary producers capture $5,000,000 \text{ J}$ of energy. If the energy transfer efficiency between trophic levels is $10\%$, and only $0.1\%$ of the tertiary consumer's energy is stored as biomass over a given period, how much energy (in J) is stored as biomass by the tertiary consumers?
Q12. (ID: ap_environmental_science_MCQ_U1S9Q12)
A detailed diagram illustrating the global hydrologic (water) cycle. Key reservoirs such as oceans, lakes, rivers, groundwater, glaciers, clouds, and living organisms are labeled. Key processes such as evaporation, transpiration, condensation, precipitation (rain, snow), runoff, infiltration, and groundwater flow are represented by arrows connecting the reservoirs. The labels for processes and reservoirs are clear.
Which of the following processes in the hydrologic cycle directly involves the conversion of liquid water into water vapor from plant leaves?
Q13. (ID: ap_environmental_science_MCQ_U1S9Q13)
A world map showing the global distribution of major terrestrial biomes. Use distinct colors or patterns to represent different biomes such as: Tropical Rainforest, Savanna, Desert, Temperate Grassland, Temperate Deciduous Forest, Boreal Forest (Taiga), Tundra, Mountains, Mediterranean (Chaparral). Include lines for the Equator, Tropic of Cancer ($23.5^\circ \text{N}$), and Tropic of Capricorn ($23.5^\circ \text{S}$). A legend associating colors/patterns with biome names is included. The map should be clear and easily interpretable.
Based on the provided world biome map, which biome is most likely found at approximately $30^\circ$ latitude, characterized by hot temperatures and low precipitation?
Q14. (ID: ap_environmental_science_MCQ_U1S9Q14)
Which of the following terms describes a sequence of organisms through which energy is transferred from one trophic level to another?
Q15. (ID: ap_environmental_science_MCQ_U1S9Q15)
A line graph showing the population sizes of a predator and prey species over time. The x-axis is
The graph illustrates population dynamics of a predator and its prey. What is the most likely long-term effect on the prey population if a new, more efficient predator is introduced into the ecosystem?
Q16. (ID: ap_environmental_science_MCQ_U1S9Q16)
A line graph showing the relationship between temperature and Gross Primary Productivity (GPP). The x-axis is
The graph displays the relationship between temperature and gross primary productivity (GPP) in a specific ecosystem. Based on the graph, at what temperature does GPP reach its peak?
Q17. (ID: ap_environmental_science_MCQ_U1S9Q17)
Which of the following organisms typically occupies the lowest trophic level in a terrestrial food web?
Q18. (ID: ap_environmental_science_MCQ_U1S9Q18)
Which of the following human activities is a significant contributor to the increase in atmospheric carbon dioxide?
Q19. (ID: ap_environmental_science_MCQ_U1S9Q19)
Which major human activity contributes to the excess nitrogen in aquatic ecosystems, leading to eutrophication?
Q20. (ID: ap_environmental_science_MCQ_U1S9Q20)
Unlike the carbon and nitrogen cycles, the phosphorus cycle does NOT typically include a significant atmospheric gaseous phase. Which of the following explains the primary reason for this difference?
Q21. (ID: ap_environmental_science_MCQ_U1S9Q21)
A cross-sectional diagram of a lake ecosystem showing its distinct zones. The diagram should clearly delineate four zones: the
The diagram shows the distinct zones of a lake ecosystem. Which zone is characterized by abundant light penetration, high biodiversity, and rooted aquatic plants?
Q22. (ID: ap_environmental_science_MCQ_U1S9Q22)
A four-level ecological energy pyramid. The bottom level is labeled
An energy pyramid for a particular ecosystem shows that primary producers contain $500,000 \text{ J}$ of energy. If the energy transfer efficiency from primary consumers to secondary consumers is $15\%$, and from secondary consumers to tertiary consumers is $10\%$, how much energy (in J) is available to the tertiary consumers?
Q23. (ID: ap_environmental_science_MCQ_U1S9Q23)
A clear and simple food web diagram. Organisms include: Grass, Berries, Grasshopper, Mouse, Rabbit, Snake, Hawk. Arrows show energy flow: Grass to Grasshopper, Mouse, Rabbit. Berries to Mouse, Rabbit. Grasshopper to Snake. Mouse to Snake, Hawk. Rabbit to Hawk. Snake to Hawk. All organisms are represented by simple drawings or text labels, with arrows indicating the direction of energy flow.
Refer to the food web. If a disease significantly reduces the population of snakes, which of the following is the most likely immediate consequence for the hawk population?
Q24. (ID: ap_environmental_science_MCQ_U1S9Q24)
The conversion of temperate grasslands to agricultural land for growing crops has significantly altered the original biome. Which of the following is the most significant long-term environmental consequence of this land-use change?
Q25. (ID: ap_environmental_science_MCQ_U1S9Q25)
Which of the following human activities directly contributes to increased groundwater depletion?

Answer Key

1. A
2. B
3. C
4. A
5. C
6. B
7. D
8. B
9. A
10. D
11. B
12. A
13. C
14. A
15. B
16. A
17. B
18. B
19. C
20. D
21. A
22. C
23. C
24. D
25. A